Mucoepidermoid carcinoma is the most common malignant salivary gland tumor. Which histopathological feature is most important in determining prognosis and guides the distinction between low-grade and high-grade variants?
- A Presence of cystic spaces
- B Proportion of mucous cells relative to epidermoid cells
- C Cystic component percentage and proportion of mucous cells, with low-grade tumors having >50% cystic areas and abundant mucous cells ✓
- D Mitotic count alone without regard to cellular composition
Correct answer: C. Cystic component percentage and proportion of mucous cells, with low-grade tumors having >50% cystic areas and abundant mucous cells
Explanation
Mucoepidermoid carcinoma grading depends on the proportion of cystic versus solid components and the relative abundance of mucous cells. Low-grade tumors have a prominent cystic component (>50%) and abundant mucous cells, carrying an excellent prognosis. High-grade tumors are predominantly solid with epidermoid predominance and fewer mucous cells, behaving aggressively. The distinction drives treatment decisions from simple excision to wide resection with possible adjuvant therapy.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.